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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111145 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 20b886e..81194ad 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -2468,6 +2468,11 @@
std::map<SCEVCallbackVH, const SCEV *>::const_iterator I = Scalars.find(V);
if (I != Scalars.end()) return I->second;
const SCEV *S = createSCEV(V);
+
+ // The process of creating a SCEV for V may have caused other SCEVs
+ // to have been created, so it's necessary to insert the new entry
+ // from scratch, rather than trying to remember the insert position
+ // above.
Scalars.insert(std::make_pair(SCEVCallbackVH(V, this), S));
return S;
}